ISLAMABAD (AP) — The United Nations and Pakistan issued an appeal Tuesday for $160 million in emergency funding to help millions affected by record-breaking floods that have killed more than 1,160 people since mid-June.

UN Secretary-General Antonio Guterres said Pakistan’s flooding, caused by weeks of unprecedented monsoon rains, were a signal to the world to step up action against climate change.

“Let’s stop sleepwalking toward the destruction of our planet by climate change,” he said in a video message to an Islamabad ceremony launching the funding appeal. “Today, it’s Pakistan. Tomorrow, it could be your country.”

Guterres will visit Pakistan on September 9 to tour areas “most impacted by this unprecedented climate catastrophe,” UN spokesman Stephane Dujarric announced Tuesday. The UN chief meet displaced families and witness how UN staff are their humanitarian partners are supporting government efforts to provide assistance, Dujarric said

More than 33 million people, or one in seven Pakistanis, have been affected by the catastrophic flooding, which has devastated a country already trying to revive a struggling economy. More than 1 million homes have been damaged or destroyed in the past two and half months, displacing millions of people. Around a half million of those displaced are living in organized camps, while others have had to find their own shelter.

Prime Minister Shahbaz Sharif said the floods badly destroyed crops, and his government was considering importing wheat to avoid any shortage of food.

Sharif said Pakistan was witnessing the worst flooding in its history and any inadvertent delay by the international community in helping victims “will be devastating for the people of Pakistan.”

He promised funds from the international community would be spent in a transparent manner and that he would ensure all aid reaches those in need. “This is my commitment,” he told reporters, saying his country is “facing the toughest moment of its history.”

Pakistan says it has received aid from some countries, and others were dispatching aid too.

On Tuesday, the US government said it would provide $30 million in assistance to help victims of the flood. According to a statement released by the US Agency for International Development, this aid will be given to Pakistan through USAID. It said the United States is deeply saddened by the devastating loss of life and livelihoods throughout Pakistan.

According to initial government estimates, the devastation caused $10 billion in damage to the economy.

“It is a preliminary estimate likely to be far greater,” Planning Minister Ahsan Iqbal told The Associated Press. More than 243 bridges and more than 5,000 kilometers (3,100 miles) of road have been damaged.

Although rains stopped three days ago, large swaths of the country remain underwater, and the main rivers, the Indus and the Swat, are still swollen. The National Disaster Management Authority on Tuesday warned emergency services to be on maximum alert, saying flood waters over the next 24 hours could cause further damage.